Active control of hybrid electric vehicle launch vibration in pure electric mode

Abstract

Sudden torque changes and torque fluctuations caused by a traction motor in HEV (hybrid electric vehicle) can result in a driveline oscillation. This paper focuses on the HEV launch vibration in pure electric mode while only the electric motor is generating output torque. A relevant mathematical model has been built based on the working principle. According to the model, the torsional vibration characteristics of the electric propulsion system have been analyzed. Two active control methods, feed-forward control (FFC) and pole placement (PP) have been applied to suppress the HEV launch vibration. However, such longitudinal vibration may still be perceived by passengers, though they can attenuate the vibration to some extent. Therefore another method, wave superposition control strategy (WSCS), has been proposed to suppress the vibration more effectively. In order to prove the control effectiveness of WSCS, all these three active control methods have been applied in simulation for a comprehensive comparison of the vibration suppression effect. Simulation results demonstrate that compared with FFC and PP, WSCS minimizes the overshoot of wheel angular acceleration (WAA) most and doesn't have much effect on the system response quickness, which can be regarded as the most effective control method.

Modeling and active control of power-split hybrid electric vehicle launch vibration

“…For the sake of designing the active controller, the moment of inertia of the planetary gear is overlooked. The dynamic relationship of the Ravigneaux planetary gear set can be replaced by equation (12).…”

“…To control this kind of torsional vibration, compared with feed-forward control and PP, WSCS has the best effect. 12 The concept of WSCS is to delay part of the input to superimpose with the original input to eliminate the output wave. The control strategy is as shown in Figure 9.…”

Adaptive torsional vibration active control for hybrid electric powertrains during start-up based on model prediction

“…Liu et al 4 suggested a method for regulating torsional vibration under parameter uncertainty conditions, integrating reference adaptive control and pole position, and the control realized the suppression of output shaft torque ripple under shock conditions. Also, other control methods like robust energy peak control, 5 feed-forward control, 6,7 PID algorithm, 8,9 linear quadratic regulator (LQR) control, 10 model predictive control (MPC), 11 and wave-electric superposition (WSCS) control 12 were also investigated.…”

Development and control of an active torsional vibration damper for vehicle powertrains

“…A wave superposition control strategy was applied to suppress the HEV launch vibration. 28 A two mass-spring damper linear model was proposed in Zhong and Wei 29 to develop a torsional vibration control algorithm based on state feedback. In Zhang et al., 30 an LQG controller with an estimator was implemented.…”